1. Field of the Invention
The present invention relates to an incubator designed to bring up premature. babies or the like, who are not capable of adjusting their temperature or the like by themselves without help, by providing them with an appropriate physiological environment.
2. Description of the Related Art
FIGS. 1-4 illustrate a related art of the incubators. As shown in FIG. 4, the incubator 11 of the related art is installed with a transparent hood 12 on a base unit 14 on a base stand 13 for accommodating a premature baby or the like, and the hood 12 is provided with a nursing window 15 for applying treatment to the accommodated baby inside the hood 12 from the outside of the hood 12 and with a transparent door 16 made of acrylic resin for opening and closing the nursing window 15. The door 16 and the hood 12 are respectively installed with rotation members 17 and bearings 18 shown in FIG. 3.
The rotation members 17 and the bearings 18 are respectively provided with cylindrical rotation shafts 21 and completely round bearing holes. 22, and, by inserting the rotation shafts 21 into the bearing holes 22, the door 16 is rotatably supported on the hood 12. Since the rotation shafts 21 are positioned outside the nursing window 15 and on the side of the base stand 13, the door 16 rotates by its own weight either in the direction to open or in the direction to close the nursing window 15 depending on whether the angle of the door 16 to the nursing window 15 is larger or smaller than a given angle, and the given angle is called a critical angle in the specification of the present invention.
The door 16 and the hood 12 are provided with door fixing devices 23, and the door fixing devices 23 consist of a nursing window opening and closing knob 24 rotatably installed on the door 16 and a nursing window opening and closing knob receiver 25 of hook shape installed on the front of the hood 12. Namely, as shown in FIG. 1, by fitting the nursing window opening and closing knob 24 into the nursing window opening and closing knob receiver 25, the door 16 is fixed by the door fixing devices 23 in the state wherein the door 16 closes the nursing window 15. The door 16 is provided with hand insertion windows 26 of one touch type, and the sides of the hood 12 are also provided with hand insertion windows (not illustrated) of gather-up type.
A bed (not illustrated) for an accommodated baby is provided inside the hood 12, and bed tilting arms 27 are provided near the nursing window 15. While the bed can be tilted by manipulating one bed tilting arm 27, the height of the bed can be adjusted by simultaneously manipulating both bed tilting arms 27. A control unit 28 is provided near one of the bed tilting arms 27, and buttons (not illustrated), displays (not illustrated) and the like to control temperature, humidity, oxygen density and the like inside the hood 12 to appropriate values for the accommodated baby are provided on the control unit 28. The base stand 13 is installed with casters 31.
In the case of the incubator 11 of the related art such as the above, when any treatment is required to apply to an accommodated baby, a doctor, a nurse or the like releases the fixation of the door 16 by rotating the nursing window opening and closing knob 24 to remove the nursing window opening and closing knob 24 from the nursing window opening and closing knob receiver 25, opens the nursing window 15 thereafter by rotating the door 16 and applies treatment to the accommodated baby. When treatment to the accommodated baby is finished, the nursing window 15 is closed by door 16 and the door 16 is fixed in the closing state by the door fixing devices 23 in a reverse order of the operation mentioned above.
After finishing treatment to the accommodated baby, however, even if operation up to closing the nursing window 15 by the door 16 is performed, it is possible to overlook the operation to fix the door 16 in a closing state by the door fixing devices 23. Besides, as shown in FIG. 2, if the nursing window opening and closing knob 24 is rotated to the same angle position as the angle position where the nursing window opening and closing knob 24 is fitted into the nursing window opening and closing knob receiver 25 during treatment to the accommodated baby for some reason, it is possible that though the operator thinks he or she has rotated the nursing window opening and closing knob 24 after the nursing window 15 was closed by the door 16, the nursing window opening and closing knob 24 has not actually been fitted into the nursing window opening and closing knob Receiver 25, and the door 16 is not fixed by the door fixing device 23 in a closing state.
Moreover, if the inside of the hood 12 is humidified to a high humidity, the inside surface of the acrylic resin made door 16 exposed to highly humid air expands, and thereby the portion of the door 16 near the nursing window opening and closing knob 24 not supported by the rotation shaft 21 warps to the outside surface. As a result, even if the operator rotates the nursing window opening and closing knob 24 after the nursing window 15 is closed by the door 16, the nursing window opening aid closing knob 24 may not be fitted into the nursing window opening and closing knob receiver 25, and thus the door 16 may not be fixed by the door fixing devices 23 in a closing state.
Furthermore, in any of these cases, if the door 16 is rotated until the angle of the door 16 to the nursing window 15 becomes smaller than the critical angle, the nursing window 15 is anyway closed by biasing force for rotating the door 16 in the direction to close the nursing window 15 by its own weight, and therefore the operator may not recognize that the door 16 is not fixed in a closing state by the door fixing devices 23.
However, since the biasing force for rotating the door 16 in the direction to close the nursing window 15 by its own weight is not strong, the door 16 is rotated to open the nursing window 15 if the door 16 is pushed from the inside of the hood 12 by the foot or the like of the accommodated baby under this state. If the nursing window 15 is kept open, the environment inside the hood 12 deviates from the physiological environment appropriate for the accommodated baby and thus it is not preferable to the accommodated baby.
It is accordingly an object of the present invention to provide the incubator wherein, even if opening and closing operation of the nursing window is not securely performed, the environment inside the hood can be maintained to the physiological environment appropriate for the accommodated baby or at least the environment inside the hood hardly deviates from the physiological environment appropriate for the accommodated baby.
In the incubator according to the present invention, if the angle of the door to the nursing window of the hood is smaller than the rotation restricting angle, the door rotation restricting means restrains the rotation by restraining the movement of the center of the rotation from the first position to the second position accompanied by the rotation of the door in the opening direction. Thus, in the case that the angle of the door is smaller than the rotation restricting angle, even if the door is pushed by the accommodated baby from the inside of the hood under the state wherein the door is not fixed by the door fixing means in a closing state, the door does not rotate in the opening direction beyond the rotation restricting angle and the angle of the door does not exceed the rotation restricting angle.
Even if the angle of the door is smaller than the rotation restricting angle, the door rotation restricting means permits the rotation of the door within the angle between the rotation restricting angle and the angle at the state wherein the door closes the nursing window. Because of this reason, even if the angle of the door is smaller than the rotation restricting angle, the nursing window can be closed by the door by further rotating the door in the closing direction, and the operator can fix the door in a closing state by the door fixing means.
Even if the angle of the door is smaller than the rotation restricting angle, the door rotation restricting means merely restrains at the rotation restricting angle the rotation by restraining the movement of the center of the rotation from the first position to the second position accompanied by the rotation of the door in the opening direction, and the supporting means also supports the door in the state wherein the center of the rotation is movable between the first position and the second position. Because of this reason, when the center of the rotation is moved from the first position to the second position by resisting the force to bias the center of the rotation to the first position, the door can be rotated in the opening direction beyond the rotation restricting angle.
On the other hand, while the door rotation restricting means rotates the door in the closing direction if the angle of the door is smaller than the critical angle, it rotates the door in the opening direction if the angle of the door is larger than the critical angle. Because of this reason, if the door is rotated in the closing direction until the angle of the door becomes smaller than the critical angle, the door rotation restricting means further rotates the door in the closing direction thereafter, making the angle of the door smaller than the rotation restricting angle as well as moving the center of the rotation from the second position toward the first position by biasing. Also, if the door is not rotated in the closing direction until the angle of the door becomes smaller than the critical angle, the door rotation restricting means rotates the door in the reverse direction or in the opening direction and thereby the nursing window is opened, and the operator can immediately recognize the opening of the nursing window and thus close the nursing window again.
Therefore, even if the operation up to closing the nursing window by the door and fixing the door in the closing state by the door fixing means is not securely performed, the angle of the door does not become larger than the rotation restricting angle, and also even if the door rotation angle is not sufficient when the nursing window is closed, the operator can immediately recognize the opening of the nursing window and thus can close the nursing window again. Because of this reason, even if opening and closing operation of the nursing window is not securely performed, the environment inside the hood can be maintained to the physiological environment appropriate for the accommodated baby or at least the environment inside the hood hardly deviates from the physiological environment appropriate for the accommodated baby.
In the preferred incubator of the present invention, on the occasion of rotation from the opening state to the closing state, the door rotation restricting means permits a movement of the center of the rotation accompanied by the rotation and thus permits the rotation. Therefore, the rotation of the door in the closing direction is not restrained by the door rotation restricting means, and the operation of closing the nursing window by rotating the door is not hindered by the door rotation restricting means.